TWI720987B - Ack policy for uplink and downlink mu ppdu - Google Patents

Abstract

A method implemented by a station (STA) in a Wireless Local Area Network (WLAN) to acknowledge a downlink (DL) multi-user (MU) physical layer (PHY) Protocol Data Unit (PPDU) transmitted by an access point (AP). The method includes receiving the DL MU PPDU, decoding a frame from the DL MU PPDU, where the frame includes an indication requesting the STA to provide a trigger-based immediate acknowledgement, determining whether trigger information for an uplink (UL) MU transmission has been obtained from the DL MU PPDU, responsive to a determination that the trigger information has been obtained from the DL MU PPDU, transmitting a trigger-based immediate acknowledgement frame to the AP during the UL MU transmission, according to the trigger information, and responsive to a determination that the trigger information has not been obtained from the DL MU PPDU, refraining from transmitting the trigger-based immediate acknowledgement frame to the AP.

Description

Confirmation policy for uplink and downlink multi-user communication protocol data unit

The embodiments of the present invention are related to the field of wireless local area network (WLAN) operation. More specifically, the embodiments of the present invention are related to a method and device for confirming a physical layer (PHY) protocol data unit (PPDU) in a multi-user (MU) transmission environment. Other embodiments are also disclosed.

The International Institute of Electrical and Electronics Engineers (IEEE) 802.11 is a set of physical and media access control (MAC) specifications for implementing wireless local area network (WLAN) communications. These specifications provide the basis for using Wi-Fi brand wireless network products managed and defined by the Wi-Fi Alliance. These specifications define the use of the 2.400-2.500GHz and 4.915-5.825GHz frequency bands. These bands are collectively referred to as 2.4 GHz and 5 GHz bands. Each frequency spectrum is subdivided into channels with a center frequency and bandwidth. The 2.4GHz band is divided into 14 channels separated by 5MHz, although some countries regulate the availability of these channels. The 5GHz frequency band is more regulated than the 2.4GHz frequency band, and the channel spacing depends on the regulation of individual countries or territories to vary across the spectrum with a minimum spacing of 5MHz.

WLAN devices are currently deployed in diverse environments. These environments are characterized by the presence of many access points (AP) and non-AP stations (STA) in a limited geographic area. Increasing interference from neighboring devices causes performance degradation. In addition, WLAN devices increasingly need to support various applications, such as video, cloud access, and uninstall. In particular, it is expected that video traffic will become the main traffic type in WLAN deployment. With the immediate needs of some of these applications, WLAN users demand improved performance.

In a working group called IEEE 802.11ax, high-performance (HE) WLAN standardization is under discussion. The goal of HE is to improve the performance felt by users who require high-capacity and high-speed services. HE can support simultaneous transmission of UL and DL MU, including multi-user multiple input multiple output (MU-MIMO) and orthogonal frequency division multiple access (OFDMA) transmission.

When the AP transmits a data frame to the STA during the DL MU transmission, the AP can ask the STA for immediate confirmation. For example, the AP can ask the STA for immediate confirmation by setting the ACK policy field of the data frame to a binary value of "00". According to the current IEEE 802.11 specifications, setting the ACK policy field in this way is to request immediate confirmation from the STA in the SU way.

The AP can transmit the DL MU physical layer (PHY) protocol data unit (PPDU) that causes the STA to provide confirmation. The STA can transmit immediate ACK, delayed ACK, ACK in SU mode, and ACK in MU mode. If multiple STAs use the same transmission resources (for example, at the same time and frequency resources) to transmit ACKs, collisions may occur.

The embodiment provides a method implemented by a base station (STA) in a wireless local area network (WLAN) to confirm the downlink (DL) multi-user (MU) physical layer (PHY) protocol data transmitted by the access point (AP) Unit (PPDU) method. The method includes receiving the DL MU PPDU and decoding a frame from the DL MU PPDU, where the frame includes requesting the STA to provide an indication of trigger-based immediate confirmation, and determining whether the trigger information for uplink (UL) MU transmission has been The DL MU PPDU is received, in response to the decision that the trigger information has been obtained from the DL MU PPDU, and based on the trigger information, a trigger-based immediate confirmation box is transmitted to the AP, and in response to the trigger information that has not yet come from the DL MU The decision obtained by the PPDU prevents the transmission of the trigger-based immediate confirmation box to the AP.

The embodiment provides a network device operating as a base station in a wireless local area network (WLAN), in which the STA is configured to confirm a downlink (DL) multi-user (MU) entity transmitted by an access point (AP) Layer (PHY) Protocol Data Unit (PPDU). The network device includes a radio frequency (RF) transceiver, a set of one or more processors, and a non-transitory machine-readable medium, with a MU confirmation module stored therein, when it is processed by the set of one or more When the device is executed, the network device receives the DL MU PPDU and decodes the frame from the DL MU PPDU when the network device operates like the STA. The frame includes an instruction to request the STA to provide an immediate confirmation based on a trigger, Determine whether the trigger information used for uplink (UL) MU transmission has been obtained from the DL MU PPDU, in response to the decision that the trigger information has been obtained from the DL MU PPDU, and transmit a trigger-based immediate confirmation box based on the trigger information To the AP and the response to the trigger information has not yet been removed from the The decision obtained by the DL MU PPDU prevents the transmission of the trigger-based immediate confirmation box to the AP.

The embodiment provides a non-transitory machine-readable storage medium having stored therein to be executed by a set of one or more processors of a network device that functions as a base station (STA) in a wireless local area network (WLAN) To confirm that the computer code of the downstream (DL) multi-user (MU) physical layer (PHY) protocol data unit (PPDU) is transmitted by the access point (AP). When the computer code is executed by the network device operating like the STA, it causes the network device to receive the DL MU PPDU and decode the frame from the DL MU PPDU, where the frame includes requesting the STA to provide a trigger-based Immediately confirm the instruction, determine whether the trigger information for uplink (UL) MU transmission has been obtained from the DL MU PPDU, respond to the decision that the trigger information has been obtained from the DL MU PPDU, and transmit according to the trigger information to trigger Based on the immediate confirmation box to the AP, and in response to the decision that the trigger information has not been obtained from the DL MU PPDU, the transmission of the trigger-based immediate confirmation box to the AP is prohibited.

The embodiment provides a method for implementing a trigger-based immediate confirmation from a base station (STA) by an access point (AP) in a wireless local area network (WLAN). The method includes generating trigger information for uplink (UL) multi-user (MU) transmission, and generating a box, where the box includes an instruction, wherein the instruction requests the STA to provide trigger-based immediate confirmation, wherein if the STA obtains The trigger information, the STA transmits a trigger-based immediate confirmation box to the AP according to the trigger information, and if the trigger information is not obtained by the STA, the STA prevents the transmission of the trigger-based stand That is, confirm the frame to the AP, and transmit a downlink (DL) MU physical layer (PHY) protocol data unit (PPDU) to the STA, where the DL MU PPDU includes the frame and the trigger information.

The embodiment provides a network device that functions like an access point (AP) in a wireless local area network (WLAN), wherein the AP is configured to trigger a trigger-based immediate confirmation from a base station (STA). The network device includes a radio frequency (RF) transceiver, a set of one or more processors, and a non-transitory machine-readable medium, with a MU confirmation module stored therein, when it is processed by the set of one or more When the device is executed, the network device when acting as an AP generates trigger information for uplink (UL) multi-user (MU) transmission, and generates a frame, where the frame includes an instruction, and the instruction requests the STA to provide a trigger -Based immediate confirmation, where if the STA obtains the trigger information, the STA transmits a trigger-based immediate confirmation box to the AP according to the trigger information, and if the STA does not obtain the trigger information, the STA stops transmitting the trigger as A basic immediate confirmation frame is transmitted to the AP, and a downlink (DL) MU physical layer (PHY) protocol data unit (PPDU) is transmitted to the STA, where the DL MU PPDU includes the frame and the trigger information.

The embodiment provides a non-transitory machine-readable storage medium having stored therein a set of one or more processors to be used as a network device that functions as an access point (AP) in a wireless local area network (WLAN) Execute computer code that triggers an immediate confirmation based on a trigger from the base station (STA). When the computer code is executed by a network device that functions as the AP, it causes the network device to generate trigger information for uplink (UL) multi-use (MU) transmission and generate a frame, where the frame includes an instruction, and the instruction request The STA provides a trigger-based immediate confirmation, where if the STA obtains the trigger information, the STA transmits a trigger-based immediate confirmation box to the AP according to the trigger information, and if the STA does not obtain the trigger information, the The STA refrains from transmitting the trigger-based immediate confirmation box to the AP and transmitting the downlink (DL) MU physical layer (PHY) protocol data unit (PPDU) to the STA, where the DL MU PPDU includes the box and the trigger information.

1: WLAN device

10: Baseband processor

11: MAC processor

12: MAC software processing unit

13: MAC hardware processing unit

15: PHY processor

20: Radio Frequency (RF) Transceiver

21: RF transmitter

22: RF receiver

30: Antenna unit

40: memory

50: Input interface unit

60: output interface unit

70: Bus

100: Transmission signal processing unit

110: encoder

120: Interleaver

130: Mapper

140: Inverse Fourier Transformer (IFT)

150: Protective Interval (GI) Inserter

200: Received signal processing unit

220: GI remover

230: Fourier converter (FT)

240: Demapper

250: Deinterleaver

260: Decoder

1200: MU confirmation (ACK) module

The present invention is illustrated by way of example rather than by way of limitation in the accompanying drawings, wherein similar reference numerals indicate similar elements. It should be noted that different references to "a" or "one" embodiment in this specification are not necessarily references to the same embodiment, and such references mean at least one. In addition, when a particular characteristic, structure, or feature is described in relation to the embodiment, whether it is clearly described or not, it is considered that it is within the knowledge of a person familiar with the present invention to influence such characteristic, structure, or feature associated with other embodiments. Or features.

FIG. 1 is a diagram depicting the operation of the MU confirmation program according to some embodiments.

FIG. 2A is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the trigger box triggers UL MU transmission.

2B is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the trigger information included in the MAC header of the data frame triggers UL MU transmission.

Fig. 3 is a diagram depicting problems that can occur during the MU verification procedure according to some embodiments.

FIG. 4 is a diagram depicting the operation of the MU confirmation program using trigger-based immediate confirmation according to some embodiments.

FIG. 5 is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which a block ACK (Block ACK) request box triggers an immediate confirmation.

FIG. 6 is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the trigger frame triggers UL MU transmission, and the ACK policy fields of the block ACK request frame and the data frame trigger immediate confirmation.

FIG. 7 is a diagram depicting problems that can occur during the MU verification procedure according to some embodiments.

FIG. 8 is a diagram depicting the operation of the MU confirmation program using trigger-based immediate confirmation according to some embodiments.

FIG. 9 is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the MU block ACK request box triggers an immediate confirmation.

Figure 10 functions as a non-AP according to some embodiments The STA's network device implements the flow chart of the processing for confirming the DL MU PPDU transmitted by the AP.

FIG. 11 is a flowchart of a process for triggering a trigger-based immediate confirmation from an STA implemented by a network device that functions as an AP according to some embodiments.

FIG. 12 is a block diagram of a network device of an STA or AP that implements MU confirmation processing and modules according to some embodiments.

Figure 13 is a block diagram of a WLAN according to some embodiments.

Fig. 14 is a schematic block diagram illustrating a transmission signal processor in a WLAN device according to some embodiments.

Fig. 15 is a schematic block diagram illustrating a received signal processing unit in a WLAN according to some embodiments.

FIG. 16 is a timing diagram of an example of carrier sensing multiple access/collision avoidance (CSMA/CA) transmission procedures according to some embodiments.

FIG. 17 is a diagram depicting the exchange of DL MU PPDU and UL MU PPDU according to some embodiments.

The embodiments disclosed herein provide a method and device for confirming a physical layer (PHY) protocol data unit (PPDU) in a multi-user transmission environment. The embodiment is to use the trigger-based immediate confirmation concept implemented by the base station (STA) in the wireless local area network (WLAN) to confirm that the access point (AP) transmits the downlink (DL) multi-user ( MU) PPDU method. Use trigger-based immediate confirmation to successfully decode the trigger information for uplink (UL) MU transmission from the DL MU PPDU transmitted by the AP during UL MU transmission according to the trigger information (for example, using configured transmission resources) The confirmation box is transmitted to the AP in MU mode. On the other hand, the STA that cannot successfully decode the trigger information from the DL MU PPDU transmitted by the AP (at least before the UL MU transmission has ended) suppresses the transmission of the confirmation box to the AP. Other embodiments are also described and declared.

In the following description, many specific details are stated. however, It is understood that the embodiments of the present invention can be practiced without these specific details. In other examples, well-known circuits, structures, and technologies are not shown in detail, so as not to obscure the understanding of this description. However, those familiar with the invention will appreciate that the invention can be practiced without such specific details. Those familiar with the present invention will be able to implement appropriate functions with the included description without undue experimentation.

The "one embodiment", "embodiment", "exemplary embodiment" and other instructions cited in this specification may include specific characteristics, structures, or features, but not every embodiment needs to include the A specific characteristic, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure, or feature is described in conjunction with the embodiment, whether it is clearly described or not, it is considered that it is within the knowledge of those familiar with the present invention to affect such feature, structure, or feature in combination with other embodiments. feature.

In the following description and the scope of patent application, the terms "couple" and "connect" and their derivatives can be used. It should be understood that these terms are not regarded as synonyms for each other. "Coupling" is used to indicate that two or more elements that may or may not be in direct physical or electrical contact with each other cooperate or interact with each other. "Connection" is used to indicate the establishment of communication between two or more components coupled to each other. As used herein, "group" refers to any positive integer item that includes one item.

Electronic devices use machine-readable media (also referred to as computer-readable media), such as non-transitory machine-readable media (for example, machine-readable storage media, such as magnetic disks, optical disks, read-only memory, flash memory) Physical devices, phase change memory) and transient machine-readable transmission media (also called carrier Wave) (for example, electric, optical, radio, acoustic, or other forms of propagating signals-such as carrier waves, infrared signals) storage and transmission (internally and/or through the network and other electronic devices) codes (which are commanded by software Composition and sometimes referred to as computer code or computer program) and/or data. Therefore, electronic devices (for example, computers) include hardware and software, such as those coupled to one or more non-transitory machine-readable storage media (to store code and data for execution on the set of processors) A set of one or more processors, and a set of one or more physical network interfaces (etc.) to establish a network connection (to use propagated signal transmission codes and/or data). In other words, typical electronic devices include non-volatile memory (including codes regardless of whether the electronic device is turned on or off) and volatile memory (for example, dynamic random access memory (DRAM), static random access memory ( SRAM)), and when the electronic device is turned on, for the execution of the processor of the electronic device, the part of the code currently being executed is copied from the slower non-volatile memory to the volatile memory (often Organized by hierarchy).

A network device (ND) is an electronic device that communicatively interconnects other electronic devices (for example, other network devices, end user devices) on the network. Some network devices are "multi-service network devices" that provide support for multiple network functions (for example, routing, bridging, switching, layer 2 aggregation, session boundary control, quality of service, and/or user management), and/ Or provide support for multi-application services (for example, data, voice, and video). Network devices or network components can include wireless communication systems, such as APs and non-AP STAs in a wireless local area network (WLAN). STA is connected to a client or user device including a client or user device connected to a WLAN via an AP WLAN and a device that communicates in it. The AP may be a specialized wireless access point network device that can communicate with other network devices in the WLAN via a wireless medium or via a wired connection. The STA or AP may be referred to as a WLAN device in this document.

Conventionally, when a WLAN device (for example, STA or AP) transmits a data frame to another WLAN device, the transmitting WLAN device can indicate its desired confirmation policy in the data frame. For example, the 2-bit ACK policy subfield in the QoS control field of the data frame (for example, bit 5 and bit 6 of the QoS control field) can be used for this purpose. Table 1 shows how the ACK policy sub-field can be interpreted by the WLAN device.

In a working group called the International Institute of Electrical and Electronics Engineers (IEEE) 802.11ax, high efficiency (HE) WLAN standardization is under discussion. HE’s goal is to improve services that require high capacity and high speed The performance perceived by the user. HE can support simultaneous transmission of UL and DL MU, including multi-user multiple input multiple output (MU-MIMO) and orthogonal frequency division multiple access (OFDMA) transmission.

When an AP (for example, a high efficiency (HE) AP) transmits a data frame to a STA (for example, a high efficiency (HE) STA) during DL MU transmission, the AP can trigger an immediate confirmation from the STA. For example, the AP can trigger an immediate confirmation from the STA by setting the ACK policy field of the data frame to a binary value of "00". According to the current IEEE 802.11 specification, setting the ACK policy field in this way is to trigger an immediate confirmation from the STA in the SU way.

Each payload in the DL MU PPDU transmitted by the AP during the DL MU transmission may include a trigger box including trigger information for UL MU transmission. The trigger information may include information about UL MU transmission, such as the transmission length of UL MU transmission and the configuration of transmission resources for UL MU transmission. The presence of the trigger box in the DL MU PPDU triggers UL MU transmission. The STA that successfully decodes the trigger information included in the trigger frame can transmit the confirmation frame (e.g., ACK box or block ACK( BA) box) to AP.

However, if the STA cannot successfully decode the trigger information, the STA can transmit the confirmation box in the SU mode, which may cause collision with other confirmation boxes transmitted by other STAs during UL MU transmission.

The embodiment overcomes the shortcomings of the existing technology by introducing a new type of confirmation policy called trigger-based immediate confirmation herein. Use trigger-based immediate acknowledgment, successfully from the DL MU transmitted by the AP The STA that decodes the trigger information for UL MU transmission based on the PPDU decodes the trigger information (for example, using the configured transmission resource) and transmits the confirmation box to the AP in the MU mode during the UL MU transmission. On the other hand, the STA that cannot successfully decode the trigger information from the DL MU PPDU transmitted by the AP (at least before the UL MU transmission has ended) suppresses the transmission of the confirmation box to the AP. In this way, STAs that cannot successfully decode the trigger information from the DL MU PPDU will avoid transmitting the confirmation box in the SU mode during UL MU transmission, and thus avoid causing collision with the confirmation box transmitted by other STAs during the UL MU transmission.

FIG. 1 is a diagram depicting the operation of the MU confirmation program according to some embodiments. For the purpose of illustration, the operations in this figure and other figures will be described in the context of a simple WLAN including an AP and at least two STAs (e.g., STA1 and STA2). However, it should be understood that the principles and concepts described herein are not limited to them. In this scheme and some other schemes (Figure 2-9), the horizontal dimension represents the time dimension, while the vertical dimension represents the frequency dimension. The AP transmits the data frame to each of STA1 and STA2 during DL MU transmission (for example, in a DL MU PPDU-which may be a DL OFDMA PPDU). The data frame for STA1 is transmitted in the first 20MHz sub-channel, and the data frame for STA2 is transmitted in the second 20MHz sub-channel. The data frame for STA1 includes an ACK policy field set to indicate the implicit block ACK request confirmation policy (for example, setting the ACK policy field to a binary value of "00"), which triggers an immediate confirmation from STA1. The data frame for STA2 includes an ACK policy field that is set to indicate the block ACK confirmation policy (for example, set the ACK policy The policy field is set to a binary value of "11"), and it solicits delayed confirmation from STA2. Using the block ACK confirmation policy, STA2 can expect a block ACK request frame from the AP in the future, and STA2 can transmit the confirmation frame to the AP in response to receiving the block ACK request frame from the AP.

Because the ACK policy field for the data frame of STA1 is set to indicate the implicit block ACK request confirmation policy, STA1 transmits the block ACK frame to the AP in the SU mode. Because the ACK policy field of the data frame for STA2 is set to indicate the block ACK confirmation policy, AP transmits the block ACK request frame to STA2, and STA2 transmits the block ACK frame in response to receiving the block ACK request frame from the AP .

FIG. 2A is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the trigger box triggers UL MU transmission. The AP transmits the trigger frame and the data frame to each of STA1 and STA2 during DL MU transmission (for example, in DL MU PPDU). The trigger frame and data frame for STA1 are transmitted in the first 20MHz sub-channel, and the trigger frame and data frame for STA2 are transmitted in the second 20MHz sub-channel. The data frame for STA1 and the data frame for STA2 trigger immediate confirmation from STA1 and STA2, respectively. Each trigger box includes trigger information for UL MU transmission. For example, the trigger information may include scheduling information for scheduling UL MU transmission. The existence of the trigger box triggers UL MU transmission. Therefore, each of STA1 and STA2 transmits the block ACK frame in the MU mode during UL MU transmission (for example, in UL MU PPDU-which can be UL OFDMA PPDU) according to trigger information (for example, using the transmission resource designated to STA). To AP.

2B is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the trigger information included in the MAC header of the data frame triggers UL MU transmission. The AP transmits data frames to each of STA1 and STA2 during DL MU transmission (for example, in a DL MU PPDU), where each data frame includes trigger information in its MAC header. The data frame for STA1 is transmitted in the first 20MHz sub-channel, and the data frame for STA2 is transmitted in the second 20MHz sub-channel. The data frame for STA1 and the data frame for STA2 trigger immediate confirmation from STA1 and STA2, respectively. The presence of trigger information in the MAC header of the data frame triggers UL MU transmission. Therefore, each of STA1 and STA2 transmits the block ACK frame to the AP in the MU mode during the UL MU transmission (for example, in the UL MU PPDU) according to the trigger information (for example, using the transmission resource assigned to the STA).

Fig. 3 is a diagram depicting problems that can occur during the MU verification procedure according to some embodiments. The AP transmits the trigger frame and the data frame to each of STA1 and STA2 during DL MU transmission (for example, in DL MU PPDU). The trigger frame and data frame for STA1 are transmitted in the first 20MHz sub-channel, and the trigger frame and data frame for STA2 are transmitted in the second 20MHz sub-channel. Each trigger box includes trigger information for UL MU transmission. The existence of the trigger box triggers UL MU transmission. Each data frame includes an ACK policy field set to indicate that an immediate confirmation is required (for example, an implicit block ACK request confirmation policy).

In this example, STA1 successfully receives and decodes the trigger information included in the trigger frame (transmitted to STA1 by the AP), and therefore During UL MU transmission, block ACK frame is transmitted to AP in MU mode. However, in this example, STA2 cannot successfully decode the trigger information included in the trigger frame (transmitted to STA2 by the AP). As a result, STA2 stops transmitting the block ACK frame to the AP in the SU mode, which collides with the block ACK frame transmitted by STA1 during UL MU transmission. The embodiments described herein solve this problem by introducing the concept of trigger-based immediate confirmation. Referring to FIG. 4, the MU confirmation procedure that uses trigger-based immediate confirmation to avoid such collisions is described.

FIG. 4 is a diagram depicting the operation of the MU confirmation program using trigger-based immediate confirmation according to some embodiments. The AP transmits the trigger frame and the data frame to each of STA1 and STA2 during DL MU transmission (for example, in DL MU PPDU). The trigger frame and data frame for STA1 are transmitted in the first 20MHz sub-channel, and the trigger frame and data frame for STA2 are transmitted in the second 20MHz sub-channel. Each trigger box includes trigger information for UL MU transmission. In one embodiment, each data frame includes an indication that the receiver (for example, STA1 or STA2 in this example) should provide a trigger-based immediate confirmation. In one embodiment, this indication is included in the ACK policy field of the data frame. For example, the ACK policy field of the data frame can be set to a binary value of "01" to indicate that the receiver should provide trigger-based immediate confirmation (the binary value of "01" is normally used for PSMP operations, but it may not be used PSMP, so this value can be used to indicate trigger-based immediate confirmation). Using trigger-based immediate confirmation, the STA that successfully decodes the trigger information for UL MU transmission from the DL MU PPDU transmitted by the AP is based on the trigger information (for example, using the configuration Transmission resources) during UL MU transmission in MU mode to transmit the confirmation box to the AP. On the other hand, the STA that cannot successfully decode the trigger information from the DL MU PPDU transmitted by the AP (at least before the UL MU transmission has ended) suppresses the transmission of the confirmation box to the AP.

In this example, STA1 successfully receives and decodes the trigger information included in the trigger frame (transmitted to STA1 by the AP), and therefore transmits the block ACK frame to the AP in the MU manner during UL MU transmission. However, in this example, STA2 cannot successfully decode the trigger information included in the trigger frame (transmitted to STA2 by the AP). According to the trigger-based immediate confirmation policy, STA2 determines whether it has successfully decoded the trigger information from the DL MU PPDU (for example, from the trigger box in the DL MU PPDU). In this example, STA2 determines that it cannot successfully decode the trigger information from the DL MU PPDU. Therefore, STA2 refrains from transmitting the confirmation box to the AP. In this way, collisions (for example, the collision described with reference to FIG. 3) can be avoided.

In the above example, the trigger information is included in the trigger box in the DL MU PPDU. However, it should be understood that the trigger information can be included in the MAC header of the data frame, otherwise it is included in the DL MU PPDU.

In the above example, the AP implicitly requests an immediate confirmation from the STA (for example, by setting the ACK policy field of the data frame). In an embodiment, the AP can obviously request an immediate confirmation from the STA by transmitting a block ACK request box in the DL MU PPDU to the STA. When the block ACK request box is used to request immediate confirmation from the STA, similar problems (for example, collisions) as described above can also occur. The area will now be described The block ACK request box is used to request an embodiment of an immediate confirmation from the STA.

FIG. 5 is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the block ACK request box triggers an immediate confirmation. The AP transmits the data frame to each of STA1 and STA2 during DL MU transmission (for example, in a DL MU PPDU-which may be a DL OFDMA PPDU). Each data frame has set its ACK policy field to indicate the block ACK confirmation policy (for example, set the ACK policy field to a binary value of "11"). The AP also transmits a block ACK request frame to STA1 during DL MU transmission. The block ACK request frame and the data frame for STA1 are transmitted in the first 20MHz sub-channel, and the data frame for STA2 is transmitted in the second 20MHz sub-channel. The block ACK request box triggers an immediate confirmation from STA1 in SU mode. Therefore, after the DL MU transmission, STA1 transmits the block ACK frame to the AP in the SU mode. Then the AP transmits a block ACK request box to STA2, which triggers an immediate confirmation from STA2 in a SU manner. Therefore, when receiving the block ACK request frame from the AP, STA2 transmits the block ACK frame to the AP.

FIG. 6 is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the trigger frame triggers UL MU transmission, and the ACK policy fields of the block ACK request frame and the data frame trigger immediate confirmation. The AP transmits a trigger frame, a block ACK request frame, and a data frame to each of STA1 and STA2 during DL MU transmission (for example, in DL MU PPDU). The trigger frame, block ACK request frame, and data frame for STA1 are transmitted in the first 20MHz sub-channel, and the trigger frame, block ACK request frame, and data frame for STA2 are transmitted in the second 20MHz sub-channel Mid pass lose. Each trigger box includes trigger information for UL MU transmission. The existence of the trigger box triggers UL MU transmission. Each data frame has set its ACK policy field to indicate the block ACK confirmation policy (for example, set the ACK policy field to a binary value of "11"). The combination of the existence of the block ACK request frame and the setting of the ACK policy field of the data frame (to indicate the block ACK confirmation policy) triggers an immediate confirmation from the STA. Therefore, each of STA1 and STA2 transmits the block ACK frame in the MU mode during UL MU transmission (for example, in UL MU PPDU-which can be UL OFDMA PPDU) according to trigger information (for example, using the transmission resource designated to STA). To AP. In an embodiment, the STA (e.g., STA1 or STA2) may transmit additional frames (e.g., one or more data frames) during UL MU transmission (if time permits).

FIG. 7 is a diagram depicting problems that can occur during the MU verification procedure according to some embodiments. The AP transmits a trigger frame, a block ACK request frame, and a data frame to each of STA1 and STA2 during DL MU transmission (for example, in DL MU PPDU). The trigger frame, block ACK request frame, and data frame for STA1 are transmitted in the first 20MHz sub-channel, and the trigger frame, block ACK request frame, and data frame for STA2 are transmitted in the second 20MHz sub-channel In the transmission. Each trigger box includes trigger information for UL MU transmission. The existence of the trigger box triggers UL MU transmission. Each data frame has set its ACK policy field to indicate the block ACK confirmation policy (for example, set the ACK policy field to a binary value of "11"). The combination of the existence of the block ACK request frame and the setting of the ACK policy field of the data frame (to indicate the block ACK confirmation policy) is triggered Immediate confirmation from STA.

In this example, STA1 successfully receives and decodes the trigger information included in the trigger frame (transmitted to STA1 by the AP), and therefore transmits the block ACK frame to the AP in the MU manner during UL MU transmission. However, in this example, STA2 cannot successfully decode the trigger information included in the trigger frame (transmitted to STA2 by the AP). As a result, STA2 stops transmitting the block ACK frame to the AP in the SU mode, which collides with the block ACK frame transmitted by STA1 during UL MU transmission. The embodiments described herein solve this problem by introducing the concept of trigger-based immediate confirmation. Referring to FIG. 8, the MU confirmation procedure using trigger-based immediate confirmation to avoid such collisions is described.

FIG. 8 is a diagram depicting the operation of the MU confirmation program using trigger-based immediate confirmation according to some embodiments. The AP transmits a trigger frame, a block ACK request frame, and a data frame to each of STA1 and STA2 during DL MU transmission (for example, in DL MU PPDU). The trigger frame, block ACK request frame, and data frame for STA1 are transmitted in the first 20MHz sub-channel, and the trigger frame, block ACK request frame, and data frame for STA2 are transmitted in the second 20MHz sub-channel In the transmission. Each trigger box includes trigger information for UL MU transmission. In one embodiment, each block ACK request box includes an indication that the receiver (for example, STA1 or STA2 in this example) should provide a trigger-based immediate confirmation. In one embodiment, this indication is included in the block ACK request (BAR) ACK policy field of the block ACK request box. For example, you can set the BAR ACK policy field of the block ACK request box to a binary bit of "1" Value to indicate that the receiver should provide trigger-based immediate confirmation (the binary value of "1" is normally used for PSMP operations, but PSMP may not be used, so this value can be used to indicate trigger-based immediate confirmation) . Each data frame has set its ACK policy field to indicate the block ACK confirmation policy (for example, set the ACK policy field to a binary value of "11"). Using trigger-based immediate confirmation, the STA that successfully decodes the trigger information for UL MU transmission from the DL MU PPDU transmitted by the AP uses the MU mode during UL MU transmission according to the trigger information (for example, using the configured transmission resource) The confirmation box is transmitted to the AP. On the other hand, the STA that cannot successfully decode the trigger information from the DL MU PPDU transmitted by the AP (at least before the UL MU transmission has ended) suppresses the transmission of the confirmation box to the AP.

In this example, STA1 successfully receives and decodes the trigger information included in the trigger frame (transmitted to STA1 by the AP), and therefore transmits the block ACK frame to the AP in the MU manner during UL MU transmission. However, in this example, STA2 cannot successfully decode the trigger information included in the trigger frame (transmitted to STA2 by the AP). According to the trigger-based immediate confirmation policy, STA2 determines whether it has successfully decoded the trigger information from the DL MU PPDU (for example, from the trigger box in the DL MU PPDU). In this example, STA2 determines that it cannot successfully decode the trigger information from the DL MU PPDU. Therefore, STA2 refrains from transmitting the confirmation box to the AP. In this way, collisions (for example, the collision described with reference to FIG. 7) can be avoided.

In the above example, the trigger information is included in the trigger box in the DL MU PPDU. However, it should be understood that trigger information can be included in the capital In the MAC header of the material frame, otherwise included in the DL MU PPDU. For example, in one embodiment, the trigger information is included in the block ACK request box. Such a box is referred to herein as a MU block ACK request box (or MU-BAR box).

FIG. 9 is a diagram depicting the operation of the MU confirmation procedure according to some embodiments, in which the MU block ACK request box triggers an immediate confirmation. The AP transmits the MU block ACK request frame and the data frame to each of STA1 and STA2 (for example, in the DL MU PPDU) during the DL MU transmission. The MU block ACK request frame and data frame for STA1 are transmitted in the first 20 MHz sub-channel, and the MU block ACK request frame and data frame for STA2 are transmitted in the second 20 MHz sub-channel. Each MU block ACK request box includes trigger information for UL MU transmission. Each data frame has set its ACK policy field to indicate the block ACK confirmation policy (for example, set the ACK policy field to a binary value of "11"). The existence of the MU block ACK request box triggers an immediate confirmation from the STA in the MU mode. Therefore, each of STA1 and STA2 transmits the block ACK frame in the MU mode during UL MU transmission (for example, in UL MU PPDU-which can be UL OFDMA PPDU) according to trigger information (for example, using the transmission resource designated to STA). To AP. In an embodiment, the STA (e.g., STA1 or STA2) may transmit additional frames (e.g., one or more data frames) during UL MU transmission (if time permits). In one embodiment, the AP can transmit a block ACK request frame (normal non-MU block ACK request frame) to the STA to trigger an immediate confirmation from the STA in the SU method, and the AP can transmit a MU block ACK frame to the STA to Use MU method Trigger an immediate confirmation from the STA.

FIG. 10 is a flowchart of processing for confirming the DL MU PPDU transmitted by the AP implemented by a network device that functions as a non-AP STA according to some embodiments. In one embodiment, the operation of the flowchart can be implemented by a network device that functions as a non-AP STA in a wireless communication network (for example, WLAN). The operations in this flowchart and other flowcharts will be described with reference to exemplary embodiments in other drawings. However, it should be understood that the operation of the flowchart can be implemented by the embodiment of the present invention other than the embodiment discussed with reference to other figures, and the embodiment of the present invention discussed with reference to these other figures can be implemented as discussed with reference to the flowchart. Operate different operations.

In one embodiment, when the STA receives the DL MU PPDU from the AP, the process is initiated (block 1010). The STA decodes the box from the DL MU PPDU, where the box includes an indication requesting the STA to provide a trigger-based immediate confirmation (block 1020). In one embodiment, the frame is a data frame. In an embodiment, the indication requesting the STA to provide a trigger-based immediate confirmation is included in the ACK policy field of the box. In one embodiment, the ACK policy field is set to a binary value of "01" to request the STA to provide an immediate confirmation based on the trigger. In one embodiment, the block is a block ACK request block. In one embodiment, the indication requesting the STA to provide a trigger-based immediate confirmation is included in the block ACK request (BAR) ACK policy field of the block ACK request box. In one embodiment, the BAR ACK policy field is set to a binary value of "1" to request the STA to provide an immediate confirmation based on the trigger. In one embodiment, the box is a MU block ACK request box.

The STA determines whether the trigger information for UL MU transmission has been (successfully) obtained from the DL MU PPDU (for example, successfully decoded) (decision block 1030). In an embodiment, the trigger information used for UL MU transmission includes information about the configuration of transmission resources used for UL MU transmission. If the STA determines that it has obtained the trigger information from the DL MU PPDU, the STA transmits the trigger-based immediate confirmation box to the AP ( For example, during UL MU transmission) (block 1040). In an embodiment, the STA transmits an immediate confirmation box based on the short inter-frame space (SITS) transmission trigger to the AP after receiving the DL MU PPDU. On the other hand, if the STA determines that the trigger information cannot be obtained from the DL MU PPDU, the STA refrains from transmitting the trigger-based immediate confirmation box to the AP (block 1050). In one embodiment, if the STA determines that it cannot get the trigger information from the DL MU PPDU, the STA waits for the block ACK request box for the frame from the AP and responds to receiving the block ACK request box to transmit the information for the frame. Confirm the box to AP. In one embodiment, if the STA determines that it cannot obtain the trigger information from the DL MU PPDU, before it receives the block ACK request frame from the AP, the STA transmits an acknowledgment frame to the AP during a subsequent transmission opportunity (for example, TXOP).

FIG. 11 is a flowchart of a process for triggering a trigger-based immediate confirmation from an STA implemented by a network device that functions as an AP according to some embodiments. In one embodiment, the operation of the flowchart can be implemented by a network device that functions like an AP in a wireless communication network (for example, WLAN).

The AP generates trigger information for UL MU transmission (block 1105). In an embodiment, the trigger information used for UL MU transmission includes information about the configuration of transmission resources used for UL MU transmission. The AP generates a frame, where the frame includes an instruction, wherein the instruction requests the STA to provide a trigger-based immediate confirmation, wherein if the STA obtains the trigger information (for example, successfully decoded), the STA transmits the trigger-based immediate confirmation according to the trigger information The frame is sent to the AP (for example, during UL MU transmission), and if the trigger information is not obtained by the STA, the STA refrains from transmitting the trigger-based immediate confirmation frame to the AP (block 1110). In one embodiment, the frame is a data frame. In an embodiment, the indication requesting the STA to provide a trigger-based immediate confirmation is included in the ACK policy field of the box. In one embodiment, the ACK policy field is set to a binary value of "01" to request the STA to provide an immediate confirmation based on the trigger. In one embodiment, the block is a block ACK request block. In an embodiment, the indication requesting the STA to provide a trigger-based immediate confirmation is included in the block ACK request (BAR) ACK policy field of the block ACK request box. In one embodiment, the BAR ACK policy field is set to a binary value of "1" to request the STA to provide an immediate confirmation based on the trigger. In one embodiment, the box is a MU block ACK request box. The STA then transmits the DL MU PPDU to the STA, where the DL MU PPDU includes the box and trigger information (block 1120).

As mentioned above, in one embodiment, the trigger information can be included in the trigger box in the DL MU PPDU. In one embodiment, a plurality of frames including a trigger frame can be included in an aggregate MPDU (A-MPDU) by aggregating the frames (for example, Mac Protocol Data Unit (MPDU)) In the DL MU PPDU. In one embodiment, at most one box including trigger information can be included in the A-MPDU. In one embodiment, the box containing trigger information should be the first or last box in the A-MPDU. In one embodiment, the ACK policy field of other boxes in the A-MPDU should not be set to indicate a normal ACK confirmation policy, an implicit block ACK request confirmation policy, or a block ACK confirmation policy. The ACK policy field of the data frame in the A-MPDU can be set to a reserved value (for example, the binary value of "01") to indicate that the receiver should provide trigger-based immediate confirmation. In this case, the confirmation behavior of the receiver depends on whether the receiver can successfully receive and decode the trigger information (for example, from the trigger box or other boxes in the A-MPDU). For example, when the frame in the DL MU PPDU includes an indication that the receiver should provide an immediate confirmation based on the trigger (for example, the ACK policy field of the data frame is set to a binary value of "01"), the confirmation behavior of the receiver can be As shown below: ACK policy is set to 01: PSMP background or UL OFDMA background

In the box tied in the PSMP background

i) When bit 6 of the frame control field is set to 1: There may be a response frame of the frame that is received, but it is neither an ACK frame nor any data frame of the +CF-ACK subtype. Set the ACK policy sub-field of the QoS CF-polling and QoS CF-ACK +CF-polling data boxes to this value.

ii) When bit 6 of the frame control field is set to 0: When the frame indicating PSMP ACK appears in the PSMP downlink transmission time (PSMP-UTT), wait for the later PSMP uplink transmission time (PSMP-UTT) receives the confirmation for it. When a box indicating PSMP ACK appears in PSMP-UTT, it will be received later in PSMP-DTT for an acknowledgment.

In the box tied in the background of UL OFDMA

i) The receiver that receives the address of the frame with the sub-channel designation information is based on the sub-channel designation information designated in the received frame, independently or as part of the A-MPDU that starts SIFS after carrying the PPDU of the frame Either way, the ACK/block ACK box is returned.

ii) The receiver who has not received the address of the frame with the sub-channel designation information will take no action other than the recording status when receiving the frame. The receiver can expect to use the procedure described in the block acknowledgment mechanism to respond to its block ACK request box in the future. But before receiving the block ACK request box in the future, when the addressed receiver gets the TXOP, it can actively send back the ACK/block ACK box. This unsolicited ACK/block ACK frame transmission is similar to the delayed block ACK policy. Through the ACK policy field, the addressed receiver knows that it is requested to return the ACK/block ACK box. But because of the loss of sub-channel designated information, the addressed receiver cannot return the ACK/block ACK box. Therefore, when the addressed receiver gets a new TXOP later, it can return an ACK/block ACK box to avoid unnecessary retransmissions from the AP.

As mentioned above, in one embodiment, the trigger information can be included in the MAC header of the frame in the DL PPDU. In this case, in one embodiment, the ACK policy field of the data frame in the A-MPDU must be set to indicate the normal ACK confirmation policy or the implicit block ACK request confirmation policy. In one embodiment, the trigger information in the MAC header of all the frames in the A-MPDU has the same information. In one embodiment, when the ACK policy field of the data frame in the A-MPDU is set to indicate no ACK acknowledgment policy, the transmission resource designation information for the receiver of the data frame is not included in the trigger information.

As mentioned above, in one embodiment, the trigger information can be included in the MU block ACK request box. In an embodiment, the MU block ACK request box may have the following format:

The BAR control field includes the number of users requesting immediate confirmation. The per-user block ACK request field and the per-user sub-channel specified field are repeated for each user. The receiver of the multi-user block ACK request box responds with the ACK frame and the block ACK frame transmitted during the UL MU transmission according to the sub-channel designation in the sub-channel designation field per user. One or more MU block ACK request boxes can be included in the DL MU PPDU. However, because the normal (non-MU) block ACK request frame can still be used to request the ACK frame or the block ACK frame transmitted in the SU mode, in one embodiment, the MU block ACK request frame and the normal block ACK request frame Should not co-exist in the same DL MU PPDU. The MU block ACK request box (and other boxes) can be included in the A-MPDU. In this case, in one embodiment, the MU block ACK request box should not be A- The first or last box in the MPDU.

In one embodiment, at most one box including trigger information can be included in the A-MPDU. In one embodiment, when the block ACK request frame is included in the A-MPDU, the ACK policy field of the data frame in the A-MPDU should be set to block ACK (because the block ACK request frame also exists in A-MPDU -MPDU). In one embodiment, the BAR ACK policy field of the block ACK request box in the A-MPDU should not be set to a binary value of "0" (normal ACK), but should be set to a reserved value (for example, "1" ”) to indicate that the receiver should provide immediate confirmation based on the trigger. In this case, the confirmation behavior of the receiver depends on whether the receiver can successfully receive and decode the trigger information (for example, from the trigger box or other boxes in the A-MPDU). For example, when the block ACK request box in the DL MU PPDU includes an indication that the receiver should provide a trigger-based immediate confirmation (for example, the BAR ACK policy field of the block ACK request box is set to a binary value of "1" ), the receiver’s confirmation behavior can be as follows: BAR ACK policy is set to 1: PSMP background or UL OFDMA background

In the box tied in the PSMP background

i) No confirmation.

The recipient does not send an immediate response when receiving the box. When the sender does not need to confirm immediately, set the BAR ACK policy subfield to this value. The value 1 is not used in the basic block ACK request box outside the PSMP sequence. The value 1 is not used in the multi-TID block ACK request box.

In the box tied in the background of UL OFDMA

i) The receiver that receives the address of the frame with the sub-channel designation information is based on the sub-channel designation information designated in the received frame, independently or as part of the A-MPDU that starts SIFS after carrying the PPDU of the frame Either way, the ACK/block ACK box is returned.

ii) The receiver who has not received the address of the frame with the sub-channel designation information will take no action other than the recording status when receiving the frame. The receiver can expect to use the procedure described in the block confirmation mechanism to respond to its block ACK request box in the future.

In one embodiment, when the block ACK request box in the DL MU PPDU includes an indication that the receiver should provide immediate confirmation in SU mode (for example, the BAR ACK policy field of the block ACK request box is set to "0". Carry value), the receiver’s confirmation behavior can be as follows: BAR ACK policy is set to 0: PSMP background or SU background

In the box tied in the PSMP background

i) Normal confirmation.

When the sender needs to confirm immediately, set the BAR ACK policy subfield to this value. The recipient sends back an ACK box (per PSMP confirmation rule).

In the box tied in the background of SU

i) The addressed receiver returns the block ACK frame either independently or as part of the A-MPDU that starts SIFS after carrying the frame's PPDU.

In one embodiment, the MU confirmation behavior is as follows. the following At most one of the boxes can exist in the A-MPDU of each intended recipient of the DL MU PPDU: i) One or more QoS data with the ACK policy field set to indicate the implicit block ACK request confirmation policy Box; ii) One or more QoS data boxes set to indicate that the receiver should provide a trigger-based immediate acknowledgement ACK policy field (for example, set the ACK policy field to a binary value of "01"); iii) Block ACK request box; and iv) MU block ACK request box.

In one embodiment, the DL MU PPDU shall not include an A-MPDU that includes one or more of the following boxes that trigger immediate acknowledgment in the SU mode: i) It has an ACK request acknowledgement policy set to indicate the implicit block One or more QoS data boxes in the ACK policy field; and ii) Block ACK request box.

In one embodiment, the DL MU PPDU may include an A-MPDU that includes one or more of the following boxes that trigger an immediate confirmation in the MU manner: i) A-MPDU with a setting to indicate that the receiver should provide a trigger-based immediate One or more QoS data frames of the confirmed ACK policy field (for example, set the ACK policy field to a binary value of "01"); and ii) MU block ACK request frame.

In one embodiment, when the DL MU PPDU includes an A-MPDU that includes a QoS data box with an ACK policy field set to indicate an implicit block ACK request confirmation policy or a block ACK request box, then the following boxes cannot exist In DL MU PPDU: i) There are one or more QoS data boxes set to indicate that the receiver should provide a trigger-based immediate acknowledgement ACK policy field (for example, set the ACK policy field to "01" The binary value of ); and ii) MU block ACK request box.

In one embodiment, when the ACK policy field of the data frame in the UL MU PPDU (transmitted from STA to AP) is set to indicate the implicit block ACK request confirmation policy (for example, the ACK policy field is set to "00 ”), the AP can respond by transmitting an ACK frame or a block ACK frame to the STA in either the SU mode or the MU mode (determined by the AP). This means that the confirmation behavior can be different depending on the transmission direction (for example, UL MU transmission vs. DL MU transmission). In one embodiment, the confirmation behavior can be summarized in Table 2 as follows:

In an embodiment, one or more block ACK request boxes may exist in the UL MU PPDU. In an embodiment, the normal (non-MU) block ACK request box included in the UL MU PPDU triggers an immediate confirmation from the AP in either the SU mode or the MU mode (determined by the AP). In one embodiment, the confirmation behavior of the block ACK request box can be summarized in Table 3 as follows:

FIG. 12 is a block diagram of a network device of an STA or AP that implements MU confirmation processing and modules according to some embodiments. In a wireless local area network (WLAN), such as the exemplary WLAN depicted in FIG. 13, a basic service set (BSS) includes a plurality of network devices referred to herein as WLAN devices. Each WLAN device may include a medium access control (MAC) layer and a physical (PHY) layer according to the IEEE 802.11 standard. Among the plurality of WLAN devices, at least one WLAN device may be an AP station (for example, access point 0 and access point 1 in FIG. 13), and other WLAN devices may be non-AP stations (non-AP STA) (for example, Stations 0-3 in Figure 13). Or, in a peer-to-peer network environment, all multiple WLAN devices may be non-AP STAs. Generally, each of the AP STA and the non-AP STA can be referred to as a station (STA) herein. However, for ease of description, only non-AP STAs are referred to as STAs in this article, but for ease of description, AP stations are referred to as APs in this article. As shown in FIG. 13, a WLAN can have any combination of STAs and APs that can form a discrete network, a peer-to-peer network, or any combination thereof. Any number of APs and STAs can be included in the WLAN, and any topology and configuration of such APs and STAs can be used in the network.

The exemplary WLAN device 1 includes a baseband processor 10, a radio frequency (RF) transceiver 20, an antenna unit 30, a memory 40, an input interface unit 50, an output interface unit 60, and a bus 70. The baseband processor 10 implements baseband signal processing, and includes a MAC processor 11 and a PHY processor 15. These processors can be any kind of integrated circuits (ICs) including general-purpose processing units or application-specific integrated circuits (ASICs). In some embodiments, the MAC processor 11 also implements the MU acknowledgement (ACK) module 1200. The MU confirmation module 1200 can implement individual functions of any combination of the embodiments described above with respect to FIGS. 1-13. In other embodiments, the MU confirmation module 1200 can be implemented by both the PHY processor 15 and the MAC processor 11 or distributed on it. The MU confirmation module 1200 can be implemented as a hardware component of either the software or the PHY processor 15 or the MAC processor 11.

In an embodiment, the MAC processor 11 may include a MAC software processing unit 12 and a MAC hardware processing unit 13. The memory 40 can store software (referred to herein as "MAC software"), including at least part of the functions of the MAC layer. The MAC software processing unit 12 executes MAC software to implement part of the functions of the MAC layer, and the MAC hardware processing unit 13 can implement the remaining functions of the MAC layer with hardware (referred to as "MAC hardware" in this document). However, the MAC processor 11 is not limited to this function allocation.

The PHY processor 15 includes a transmission signal processing unit 100 and a reception signal processing unit 200 described further below with reference to FIGS. 9 and 10.

Baseband processor 10, memory 40, input interface unit 50 and the output interface unit 60 can communicate with each other via the bus 70. The radio frequency (RF) transceiver 20 includes an RF transmitter 21 and an RF receiver 22. The memory 40 can further store the operating system and application programs. In some embodiments, the memory can store record information related to the retrieved frame. The input interface unit 50 receives information from the user, and the output interface unit 60 outputs the information to the user.

The antenna unit 30 includes one or more antennas. When a MIMO or MU-MIMO system is used, the antenna unit 30 may include a plurality of antennas.

Fig. 14 is a schematic block diagram illustrating a transmission signal processor in a WLAN device according to some embodiments. With reference to the above drawings, the transmission signal processing unit 100 includes an encoder 110, an interleaver 120, a mapper 130, an inverse Fourier transform (IFT) 140, and a guard interval (GI) inserter 150. The encoder 110 encodes input data. For example, the encoder 110 may be a forward error correction (FEC) encoder. The FEC encoder may include a binary convolutional code (BCC) encoder, followed by a puncture device, or may include a low-density parity check (LDPC) encoder.

The transmission signal processing unit 100 may further include a mixer for mixing the input data before encoding, so as to reduce the possibility of a long sequence of 0s or 1s. If BCC encoding is used in the encoder 110, the transmission signal processing unit 100 may further include an encoder parser for demultiplexing code bits in the complex BCC encoder. If LDPC encoding is used in the encoder 110, the transmission signal processing unit 100 may not use an encoder parser.

The interleaver 120 will output the bits of each stream from the encoder Interleave to change the bit order. Interleaving can only be applied when BCC encoding is used. The mapper 130 maps the bit sequence output from the interleaver to cluster points. If the LDPC coding is used in the encoder 110, in addition to cluster mapping, the mapper 130 can further implement LDPC tone color mapping.

When using multiple input-multiple output (MIMO) or multiple user (MU)-MIMO, the transmission signal processing unit 100 may use a plurality of interleavers 120 and a plurality of mappers 130 _{corresponding to the number of spatial streams N SS.} In this case, the transmission signal processing unit 100 may further include a stream parser for dividing the output of the BCC encoder or LDPC encoder into blocks that are sent to different interleavers 120 or mappers 130. The transmission signal processing unit 100 may further include _{a space-time block code (STBC) encoder for dispersing the aggregator from the N SS} spatial stream to the N _STS space-time stream, and a space-time block code (STBC) encoder for mapping the space-time stream into a transmission chain Space mapper. The spatial mapper can use direct mapping, spatial expansion, or bundling.

The IFT 140 converts the square of the gathering point output from the mapper 130 or the spatial mapper into a time domain square (ie, a symbol) by using an inverse discrete Fourier transform (IDFT) or an inverse fast Fourier transform (IFFT). If the STBC encoder and the spatial mapper are used, the inverse Fourier converter 140 can be set for each transmission chain.

When using MIMO or MU-MIMO, the transmission signal processing unit 100 may insert cyclic shift diversity (CSD) to prevent accidental bunching. CSD insertion may occur before or after the inverse Fourier transform 140. CSD can be specified for each transmission chain or can be specified for each space-time stream. Alternatively, CSD can be applied as part of the spatial mapper. When using In the case of MU-MIMO, some of the blocks before the spatial mapper can be provided to each user.

The GI inserter 150 puts the GI in front of the symbol. The transmission signal processing unit 100 may selectively implement windowing after inserting the GI to smooth the edges of each symbol. The RF transmitter 21 converts the symbol into an RF signal and transmits the RF signal via the antenna unit 30. When MIMO or MU-MIMO is used, the GI inserter 150 and the RF transmitter 21 can be set for each transmission chain.

Fig. 15 is a schematic block diagram illustrating a received signal processing unit in a WLAN according to some embodiments. 15, the received signal processing unit 200 includes a GI remover 220, a Fourier transform (FT) 230, a demapper 240, a deinterleaver 250, and a decoder 260.

The RF receiver 22 receives the RF signal via the antenna unit 30 and converts the RF signal into a symbol. The GI remover 220 removes the GI from the symbol. When MIMO or MU-MIMO is used, the RF receiver 22 and the GI remover 220 can be provided for each receiving chain.

The FT 230 converts symbols (that is, time-domain blocks) into blocks of gathering points by using Discrete Fourier Transform (DFT) or Fast Fourier Transform (FFT). The Fourier converter 230 can be provided for each receiving chain.

When MIMO or MU-MIMO is used, the received signal processing unit 200 may use a spatial demapper for converting the Fourier-transformed receiving chain into an aggregation point of the space-time stream and a spatial demapper for de-mapping the aggregation point from the space-time stream. Decompose to the STBC decoder in the spatial stream.

The demapper 240 demaps the aggregation points output from the Fourier converter 230 or the STBC decoder into a bit stream. If LDPC is used Code, the demapper 240 may perform LDPC tone demapping before the aggregation demapping. The deinterleaver 250 deinterleaves the bits of each stream output from the demapper 240. Deinterlacing can only be applied when BCC encoding is used.

When MIMO or MU-MIMO is used, the received signal processing unit 200 may use a plurality of demappers 240 and a plurality of deinterleavers 250 corresponding to the number of spatial streams. In this case, the received signal processing unit 200 may further include a stream analyzer for combining the streams output from the deinterleaver 250.

The decoder 260 decodes the stream output from the deinterleaver 250 or the stream dissector. For example, the decoder 260 may be an FEC decoder. The FEC decoder may include a BCC decoder or an LDPC decoder. The received signal processing unit 200 may further include a de-mixer for de-mixing the decoded data. If BCC decoding is used in the decoder 260, the received signal processing unit 200 may further include an encoder dissector that multiplexes the data decoded by a plurality of BCC decoders. If LDPC decoding is used in the decoder 260, the received signal processing unit 200 may not use an encoder dissect parser.

FIG. 16 is a timing diagram of an example of carrier sensing multiple access/collision avoidance (CSMA/CA) transmission procedures according to some embodiments. In the illustrative example, STA1 is a transmitting WLAN device for transmitting data, STA2 is a receiving WLAN device for receiving the data, and STA3 is a WLAN device, which can be located in the transmission frame from STA1 and/or the transmission frame from STA2. The area that can be received by this WLAN device.

STA1 can determine whether the channel is busy through carrier sensing. STA1 can be determined based on the signal quality on the channel or the signal association in the channel Channel occupancy, or the channel occupancy can be determined by using a network configuration vector (NAV) timer.

When it is determined that the channel is not used by other devices during the DIFS (that is, the channel is idle), STA1 can transmit the RTS frame to STA2 after implementing the back shift. When receiving the RTS box, STA2 can transmit the CTS box as a response to the CTS box after SIFS. When STA3 receives the RTS frame, it can set the NAV timer to the transmission duration of the subsequent transmission frame by using the duration information included in the RTS frame (for example, the duration of the SIFS + the duration of the CTS frame + the duration of the SIFS + Data frame duration + SIFS + ACK frame duration). When STA3 receives the CTS frame, it can set the NAV timer to the transmission duration of the subsequent transmission frame by using the duration information included in the RTS frame (for example, the duration of SIFS+the duration of the data frame+SIFS +ACK box duration). When a new frame is received before the NAV adjuster times out, STA3 can update the NAV timer by using the duration information included in the new frame. STA3 will not attempt to access the channel before the NAV timer expires.

When STA1 receives the CTS frame from STA2, it can transmit the data frame to STA2 after the SIFS has elapsed from the time when the CTS frame has been completely received. When successfully receiving the data frame, STA2 can transmit an ACK frame as a response to the data frame after SIFS.

When the NAV timer expires, STA3 can determine whether the channel is busy by using carrier sensing technology. When it is determined that the channel is not used by other devices during the DIFS and after the NAV timer has expired, STA3 can try channel access after the contention window that is shifted back randomly has elapsed.

The solution provided in this article has been described with reference to the wireless LAN system; however, it should be understood that the solution can also be applied to other network environments, such as cellular telecommunication networks, wired networks, and similar communication networks.

FIG. 17 is a diagram depicting the exchange of DL MU PPDU and UL MU PPDU according to some embodiments. In the illustrative example, the AP transmits the DL OFDMA PPDU in the high efficiency (HE) PPDU format. The HE PPDU format includes traditional preamble, HE preamble, and data sent to each STA. The AP transmits data for STA1, STA2, STA3, STA4, STAS, STA6, and STA7 via 5MHz, 5MHz, 10MHz, 5MHz, 5MHz, 5MHz, and 5MHz sub-channels respectively. In this example, after receiving the SIFS time of the DL OFDMA PPDU, STA1 and STA4 transmit the control response frame in the UL OFDMA PPDU in the HE PPDU format (for example, via the 20MHz and 20MHz secondary channels, respectively).

Embodiments of the present invention may be articles in which a non-transitory machine-readable medium (such as a microelectronic memory) has one or more programmatic data processing components stored thereon (generally referred to herein as a "processor" ) To implement the instructions for the above operations. In other embodiments, some of these operations can be implemented by specific hardware components that include hard-wired logic (for example, dedicated digital filter blocks and state machines). These operations can additionally be implemented by any combination of programmed data processing components and fixed hard-wired circuit components.

Part of the content of the above-mentioned embodiment has been presented based on the algorithm and symbolic representation of the operation on the data bit in the computer memory. These calculation descriptions and representations are methods used by people familiar with conference technology. In order to most effectively convey the substance of their work to other people who are familiar with this technology. In this article, and generally, algorithms are conceived as a series of self-consistent operations that lead to a desired result. These operations require actual manipulation of physical quantities. However, it should be borne in mind that all these and similar terms are related to appropriate physical quantities and are only convenient labels applied to these equivalent quantities. Unless specifically stated otherwise, it is obvious from the above discussion that it is understood that throughout this description, the use of terms, such as the terms set forth in the scope of the following patent applications, refers to the actions and processing of conference devices or similar electronic computing devices , Which manipulates and transforms data expressed as physical (electronic) quantities in the register and memory of the conference device into the memory or register of the conference device or other such information storage, transmission or display device Other data similarly expressed as physical quantities.

Although the flowchart in the drawings shows a specific order of operations performed by a specific embodiment of the present invention herein, it should be understood that this order is an example (for example, alternative embodiments may perform operations in a different order, combine specific operations, overlap specific operations, etc. ).

While the present invention has been described in several embodiments in sequence, those skilled in the art will recognize that the present invention is not limited to the described embodiments, and can be used within the spirit and scope of the attached patent application. Modifications and changes are implemented. Therefore, this description is to be regarded as illustrative and not restrictive.

Claims (20)

A network device used as a base station (STA) in a wireless local area network (WLAN). The STA is configured to confirm the downlink (DL) multi-user (MU) physical layer ( PHY) Protocol Data Unit (PPDU), including: one or more memories; and one or more processors coupled to the one or more memories, and the one or more processors are configured to enable the network The device is used as the STA to perform operations, including: receiving the DL MU PPDU; decoding the frame from the DL MU PPDU; determining whether the ACK policy field of the frame has been set to the binary value '01', where the binary value '01' indicates to the STA to provide an immediate confirmation based on the trigger; to determine whether the trigger information for uplink (UL) MU transmission has been obtained from the DL MU PPDU; the ACK policy field in response to the box has been set to The decision of the binary value '01' and the decision that the trigger information has been obtained from the DL MU PPDU, according to the trigger information, transmit a trigger-based immediate confirmation box to the AP; and respond to the ACK policy column of the box The decision that the bit has been set to the binary value '01' and the decision that the trigger information has not yet been obtained from the DL MU PPDU shall prevent the transmission of the trigger-based immediate confirmation box to the AP. Such as the network device of the first item of the patent application, the binary entry The bit value '01' is a reserved value for confirmation in the background of multiple polling power saving (PSMP). For example, in the network device of the second item of the scope of patent application, the ACK policy field set to a binary value of '01' in the PSMP background indicates to the STA when bit 6 of the frame control field is set to '1' At the time, the response box to the receiving box is allowed, but it is neither a confirmation box nor any contention free-acknowledgement (+CF-Ack) sub-type data box. For example, in the network device of the third item of the scope of patent application, the ACK policy field that is set to the binary value of '01' in the PSMP background indicates to the STA when bit 6 of the frame control field is set to '0. At the time of', the confirmation for the frame is received in the PSMP downlink transmission time (PSMP-DTT), and it is received in the later PSMP uplink transmission time (PSMP-UTT). For example, the network device of the first item in the scope of patent application, where the frame is a data frame. For example, in the network device of the first item of the scope of the patent application, preventing the transmission of the trigger-based immediate confirmation box includes: waiting for the block ACK request box for the block; and in response to receiving the block ACK request box, transmitting The confirmation box for the box to the AP. For example, in the network device of the first item of the patent application, transmitting the trigger-based immediate confirmation box includes: after receiving the DL MU PPDU, the short interframe space (SIFS) transmits the trigger-based immediate confirmation box . Such as the network device of the first item in the scope of patent application, where the trigger The information includes information about the configuration of the transmission resource used for the UL MU transmission, and the transmission of the trigger-based immediate confirmation box includes: transmitting the trigger-based immediate by using the transmission resource configured for the STA Confirmation box. A type of downlink (DL) multi-user (MU) physical layer (PHY) protocol data unit (PPDU) implemented by a base station (STA) in a wireless local area network (WLAN) to confirm transmission by an access point (AP) ) Method, the method includes: receiving the DL MU PPDU; decoding the frame from the DL MU PPDU; determining whether the ACK policy field of the frame has been set to a binary value of '01', where the binary value of '01' indicates Until the STA provides a trigger-based immediate confirmation; determines whether the trigger information for uplink (UL) MU transmission has been obtained from the DL MU PPDU; the ACK policy field in response to the box has been set to a binary value' 01' decision and the decision that the trigger information has been obtained from the DL MU PPDU, according to the trigger information, a trigger-based immediate confirmation box is transmitted to the AP; and the ACK policy field in response to the box has been set to The decision of the binary value of '01' and the decision that the trigger information has not been obtained from the DL MU PPDU shall prevent the transmission of the trigger-based immediate confirmation box to the AP. For example, the method of item 9 in the scope of patent application, where the binary value '01' is a reserved value for confirmation in the background of multiple polling power saving (PSMP). For example, in the method of item 10 of the scope of patent application, the ACK policy field set to a binary value of '01' in the PSMP background indicates to the STA that when bit 6 of the frame control field is set to '1', The response box to the receiving box is allowed, but it is neither a confirmation box nor any contention-free cycle response (ContentionFree-Acknowledgement (+CF-Ack)) sub-type data box. For example, in the method of item 11 of the scope of patent application, the ACK policy field set to a binary value of '01' in the PSMP background indicates to the STA when bit 6 of the box control field is set to '0' , The confirmation for receiving the frame in the PSMP downlink transmission time (PSMP-DTT) will be received in the later PSMP uplink transmission time (PSMP-UTT). Such as the method of claim 9 in the scope of patent application, where the frame is a data frame network device. For example, in the method of item 9 of the scope of the patent application, preventing the transmission of the trigger-based immediate confirmation box includes: waiting for the block ACK request box for the block; and in response to receiving the block ACK request box, transmitting the The confirmation box of the box to the AP. For example, in the method of claim 9, wherein transmitting the trigger-based immediate confirmation box includes: after receiving the DL MU PPDU, transmitting the trigger-based immediate confirmation box to the short inter-frame space (SIFS). Such as the method of claim 9 in the scope of patent application, where the trigger information Including information about the configuration of the transmission resource used for the UL MU transmission, and transmitting the trigger-based immediate confirmation box includes: transmitting the trigger-based immediate confirmation by using the transmission resource configured for the STA frame. A method of implementing trigger-based immediate confirmation from the base station (STA) by the access point (AP) in the wireless local area network (WLAN). The method includes: generating for uplink (UL) multi-use Trigger information transmitted by the MU; a box is generated, in which the ACK policy field of the box is set to a binary value of '01' to request the STA to provide immediate confirmation based on the trigger, where if the trigger information is determined by the If the STA obtains it, the STA transmits a trigger-based immediate confirmation box to the AP according to the trigger information, and if the trigger information is not obtained by the STA, the STA refrains from transmitting the trigger-based immediate confirmation box to the AP AP; and transmit a downlink (DL) MU entity (PHY) protocol data unit (PPDU) to the STA, where the DL MU PPDU includes the frame and the trigger information. For example, in the method of item 17 in the scope of the patent application, the binary value '01' is a reserved value for confirmation in the background of multiple polling power saving (PSMP). For example, the method of item 18 of the scope of patent application, in which the ACK policy field set to the binary value of '01' in the PSMP background is sent to the STA Indicates that when bit 6 of the frame control field is set to '1', the response frame to the receiving frame is allowed but it is neither a confirmation frame nor any contention-free cycle response (ContentionFree-Acknowledgement(+CF-Ack)) The data frame of the sub-category. Such as the method of item 19 of the scope of patent application, in which the ACK policy field set to a binary value of '01' in the PSMP background indicates to the STA when bit 6 of the box control field is set to '0' , The confirmation for the frame is received in the PSMP downlink transmission time (PSMP-DTT), and it is received in the later PSMP uplink transmission time (PSMP-UTT).

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